Arm length - Measure from crown to wrist (shoulder seam to cuff).  You can measure a jacket you own and like the fit of to get this measurement.

Shoulder to cuff & inner leg length measurements are important as these  will decide if you need a Short / Regular or Long fit. ( See below for detailed sizes)

 Chest Size - Measure around the broadest part of the chest  keeping the tape up under the arms. Keep one finger between the tape measure and the body and breath in. Whatever that measurement is then that is your chest size.

PLEASE NOTE:   A suit jacket that is a 38" chest fit will measure 1 - 5 " more to allow room for movement
( and breathing !) 
Depending on style and personal preference of fit a 38 chest fit will measure 39" - 42" approx.
 
When sizing garments we take into account how they are intended to be worn and size accordingly. Many vintage items have no size label and those that do are often outdated as vintage clothing was sized smaller in the past, so we size all garments ourselves to give as accurate a size as possible.

When buying a tweed jacket it's best to consider how you will wear it. Will you be wearing it for casual wear with a tee shirt / shirt or will you be wearing it for country sports ? ( Hunting, shooting, fishing etc. )
If you are going to be wearing your tweed jacket casually then a jacket that measures 3 to 4 inches more than your own chest measurement is fine. However if you need more room to move for a country sport and will be wearing a shirt, tweed waistcoat, etc. then 4 to 5 inches may be more comfortable to wear.

 Even a  slim / skinny fit 60s/70s suit needs some movement room especially if it is a 3 piece as you will have a waistcoat to consider also (although these were made to be a fairly tight fit).

 Waistcoats usually measure approx 0"-2" more than actual chest size. 

Waist Size -  For trousers measure 1 inch above the hip bone. Men tend to breathe in when getting measured so ensure you are relaxed and breathing out. For 70s hipsters, measure slightly lower .


 Height - Measure head to toe.

 Jacket / Waistcoat Length - Measure from the back of the neck to appropriate point. 


Outside Leg - Measure from waist to ankle or normal position you like to wear your trousers. If you require this measurement please let me know. 

Inside Leg - Measure crotch to ankle.